LG FFH-286A Service Manual page 21

IC102 Troubleshooting
Is power supplied to pin8(10V)
YES
Check the waveform of Pin 20, 21
YES
Check the output of Pin 16, 17
YES
END
IC103 Troubleshooting
Check the power supplying to pin 17
YES
Check the oscillation of X104
YES
Check the waveform of CE, DI, DO, CLK
YES
Is the normal ?
YES
END
NO
NO
Check the FM(TUN101) & AM(L107)
NO
Check the "Low" of Pin 13
NO
NO
Check the line or refer to "IC 301
Troubleshooting"
NO
CE: Chip Enable
DI: Data Input(from u-com)
DO: Data Output(to u-com)
CLK: Tuner mode clock
NO
- 2-14 -
Refer to "Power Circuit
Troubleshooting"
NO
Replace the IC102
NO
YES
Replace the IC102
Refer to "Power Circuit
Troubleshooting"
Replace the X104
Replace the IC103
Refer to "IC103
Troubleshooting"